Chandra X-Ray Observatory

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Chandra X-Ray Observatory

An orbiting X-ray astronomy observatory launched by NASA in July 1999 as the third of its Great Observatories. Chandra, which takes its name from the 20th-century Indian-born US astrophysicist Subrahmanyan Chandrasekhar, was originally developed as one of the craft making up NASA's Advanced X-Ray Astrophysics Facility (see AXAF); dubbed AXAF-I and renamed after its launch, Chandra was equipped for high-resolution X-ray imaging and was deployed by the space shuttle Columbia into a highly eccentric orbit (apogee 140 161 km, inclination 28.5°) that has allowed long periods of observation unimpeded by Earth shadowing. Chandra's optics consist of four nested pairs of grazing incidence paraboloid and hyperboloid mirrors, each having an outer diameter of 1.2 meters and a focal length of 10 meters. With its Advanced Charged Couple Imaging Spectrometer (ACIS) and its high-resolution camera using large field-of-view microchannel plates to make X-ray images, Chandra's optical system achieves an angular resolution of 0.5 arcseconds over an operating range of 0.2–10 keV. Its high- and low-energy transmission gratings provide impressive spectral resolution throughout the range 0.09–10 keV.

Chandra has been called the most sophisticated X-ray observatory of its time, providing images of unprecedented detail at resolutions that are claimed to be about 50 times better than those achieved by ROSAT, the best X-ray astronomy satellite prior to 1999. In its first five years, Chandra has begun to penetrate the hottest, most energetic regions of the Universe. In particular, it has advanced our knowledge of black holes, discovering among many other things how fast they spin, finding evidence of a star torn apart by a black hole, and emphatically confirming the reality of the event horizon. It has revealed enormous tracts of hot gas, billions of parsecs distant and radiating at temperatures of tens of millions of degrees K. It has provided startling new images of supernova remnants such as the Crab Nebula, with its restless pulsar, showing intricate details never suspected before. It has made new studies of star-forming regions such as the Orion Nebula and analyzed the effects of galaxy collisions and the merging of galaxy clusters. Most notably, it has gathered direct evidence of dark energy and the expansion of the Universe.

Collins Dictionary of Astronomy © Market House Books Ltd, 2006
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The space agency recently celebrated the (https://www.ibtimes.com/nasa-releases-new-breathtaking-space-photos-galaxy-clusters-supernova-explosions-2808355) 20th anniversary of the Chandra Observatory. Aside from the latest image of the Rosette Nebula, NASA also released a (https://www.nasa.gov/mission_pages/chandra/images/20th_anniversary_gallery.html) new gallery featuring the other beautiful photos taken by the satellite.
Working with scientists in Germany and Spain, the Clemson researchers studied data from the Chandra observatory and proved that the X-ray source was a stellar mass black hole that is swallowing material at very high rates.
Several telescopes were used to build a picture of the violent event, including the Chandra observatory, Hubble Space Telescope, and Spitzer Space Telescope, as well as Earthbound observatories such as the Very Large Array telescope in New Mexico and Britain's Multi-Element Radio Linked Interferometer Network or MERLIN telescopes.
Finally, the sharp eye of the Chandra observatory failed to find a pulsar--the clearest sign of a type 2 supernova.
A composite picture of several x-ray images taken at NASA's Chandra observatory reveals hundreds of white dwarf stars, neutron stars and black holes, bathed in an incandescent fog of multi-million degree gas.
By contrast, NASA has extended the Chandra observatory's primary mission until 2009--and the flight may continue thereafter.
The "bubble" is 23 light-years across and continues to expand at a rate of over 11 million miles per hour (5,000 kilometers per second), according to the (http://chandra.harvard.edu/photo/2010/snr0509/) Chandra observatory website.
Marianne's research -- which was carried out under the supervision of SRON researcher Peter Jonker -- suggests this discovery may be only the tip of the iceberg, with others subject to future confirmation using the Chandra Observatory.
But three weeks later Wallace Tucker, science spokesman for the Chandra XAn ray Center, announced that the flickering had proved to be a spurious effect in a detector aboard the Chandra observatory. That left the upper limit on the hole's mass as high as a few million Suns.
Instead, they talked a lot about the Chandra Observatory, stored aboard Columbia.
Though scientists have seen just a single planet orbiting Proxima Centauri, the data collected by NASA's Chandra observatory suggests the neighborhood around the star's companion (Alpha Centauri A, B) looks more friendly to life.
The Chandra observatory, though equipped with a better mirror and CCD imagers like the ones that ASCA pioneered, is seldom used for the long observations of sources that ASCA frequently conducted.